CAPE CANAVERAL - NASA is now aiming for a late Friday night launch for space shuttle Discovery and her crew.
A fuel valve that plays a critical role in filling and draining the shuttle's large external fuel tank failed during the pre-launch fueling process Tuesday afternoon. Data from the shuttle indicated that it would not close, forcing NASA to scrub the overnight launch attempt.
During tests Wednesday evening, the valve cycled correctly each time it was commanded to. That led program managers to resume the countdown just before 9 a.m. today, but three hours later they decided to wait another 24 hours to allow for more engineering analysis.
Discovery is ready for a 13-day mission to the international space station mission. In addition to delivering 17,000 pounds of supplies and equipment, the shuttle will also drop off Clearwater's Nicole Stott for her three-month stay on the station.
Launch is now scheduled for 11:59 p.m. Friday night. The most recent forecast called for a 60-percent chance of good weather, however Discovery's first launch attempt early Tuesday morning was delayed by weather despite an 80-percent forecast of good weather.
NASA is up against an August 31 deadline to get this mission off the ground, or they will have to stand down until October.